Book Image

GNU/Linux Rapid Embedded Programming

By : Rodolfo Giometti
Book Image

GNU/Linux Rapid Embedded Programming

By: Rodolfo Giometti

Overview of this book

Embedded computers have become very complex in the last few years and developers need to easily manage them by focusing on how to solve a problem without wasting time in finding supported peripherals or learning how to manage them. The main challenge with experienced embedded programmers and engineers is really how long it takes to turn an idea into reality, and we show you exactly how to do it. This book shows how to interact with external environments through specific peripherals used in the industry. We will use the latest Linux kernel release 4.4.x and Debian/Ubuntu distributions (with embedded distributions like OpenWrt and Yocto). The book will present popular boards in the industry that are user-friendly to base the rest of the projects on - BeagleBone Black, SAMA5D3 Xplained, Wandboard and system-on-chip manufacturers. Readers will be able to take their first steps in programming the embedded platforms, using C, Bash, and Python/PHP languages in order to get access to the external peripherals. More about using and programming device driver and accessing the peripherals will be covered to lay a strong foundation. The readers will learn how to read/write data from/to the external environment by using both C programs or a scripting language (Bash/PHP/Python) and how to configure a device driver for a specific hardware. After finishing this book, the readers will be able to gain a good knowledge level and understanding of writing, configuring, and managing drivers, controlling and monitoring applications with the help of efficient/quick programming and will be able to apply these skills into real-world projects.
Table of Contents (26 chapters)
GNU/Linux Rapid Embedded Programming
Credits
About the Author
About the Reviewer
www.PacktPub.com
Customer Feedback
Preface

What is an analog-to-digital converter device?


An analog-to-digital converter (ADC) is a device that can convert an analog signal into a digital one. The conversion involves quantization of the input, and instead of continuously performing the conversion, an ADC does the conversion periodically by sampling the input at specific moments. The result is a sequence of digital values (having a well-defined resolution, that is, the number of bits used to represent the converted digital value) that have been converted from a continuous time and continuous amplitude analog signal to a discrete time and discrete amplitude digital signal.

As a simple example, in the following graph, there is an 8-level ADC coding scheme where the input signal Vin is referred to with the Vref signal (the maximum allowed input value) and then encoded into a binary number:

Tip

The small circles mean that the analog values at 1/8, 2/8, and so on are mapped using the bigger value. For example, if Vin/Vref = 1/8, the corresponding...